It has been rightly said in this forum and others that we are not likely to see another villain performance on par with Heath Ledger's Joker. I doubt that many actors could match the rumbling tension and hysterical terror that he brings to most of the film, and even if they did, it would more likely be mimicry than art. So how to complete the trilogy without jumping the shark?

Perhaps the last scenes in this movie provide some guidance and a hint of what's to come. (Spoiler Alert, by the way) Batman is on the run now. He is an enemy of the law and a public that is frightened into a frenzy by the scourge of violence for which they hold him increasingly responsible. Even though he was technically an outlaw vigilante in the first two movies, the police gave him wide latitude except when they felt that he was interfering with them. This will not be the case anymore. Commissioner Gordon cannot cover his regular Batman meetings with coy excuses to colleagues anymore, and Batman cannot waltz into the police station to beat up suspects in the interrogation room.

As far as everyone in Gotham knows, Batman has murdered policemen. There is no coming back from that. An angry and hysterical public will be pushing an angry and vindictive police department to bring them Batman's head, unmasked.

Batman might then become not only a lonely vigilante but a hounded revolutionary - an slightly different archetype with a history in film as long and distinguished as that of the vigilante. He would be fighting against injustice that is even more overpowering when his whole world is against him, and even his old friends are hardly able to help.

This is all well, but we need a central figure to give these malevolent clouds a face and voice. He would not be a abhorrent lunatic like the Joker, who could not even show his face in public without eliciting screams. Instead he would be a cunning political figure who feeds off of physical and moral corruption, seducing the public with powerful rhetoric that stokes their fears of the violence all around them, then adds to the chaos through a shadowy underworld network, only to feed off their fears again. Even in public, no one would ever mistake him for an attractive man, but there would be a sinister, hypnotic quality to him through which, if it were executed correctly, the audience might be struck with the dawning, horrifying realization that this cynical monster is less like some bizarre maniac and very much like someone you might find on your AM dial, stoking your worst fears and feeding on your panic. He giggles, knowing that by poisoning the public discourse he brings civilization crashing down on our heads while he cashes our checks. It is a subtler kind of horror, probably to be lost completely on anyone under the age of 13. For the rest of us, though, it might provide enough fodder for conversation as the excellent The Dark Knight has.

Well, it's an idea. I just wonder who could play the Penguin these days. If only there were some people out there who had some nominations...

Not sure who started the rumours, but Philip Seymour Hoffman ("Capote") was mentioned as a possible Penguin -- to possibly appear in "The Dark Knight."

Christopher Nolan acknowledged the rumour by saying that Hoffman was a great actor who would make a great Penguin...but he would not be in "The Dark Night."

Of course, the first rumoured Penguin in the Burton films was Dustin Hoffman...and we ended up with Danny De Vito.

Anyone who is familiar with Frank Miller's rendition of the Batman (The Dark Knight Returns, Batman Year One) will recognize much of those stories in Nolan's vision. The scene with Batman saving Gordon's son was almost a panel by panel lift from Year One.

A truly great sequel to would be to envision "the Dark Knight Returns". Much of what the OP talked about happens, along with Batman coming out of retirement, the Joker waking from a coma as soon as he does, and lastly, Batman kicking Superman's ass.

Best comic book ever.